Definition

Narcolepsy is a chronic sleep boundary disorder that affects the control of sleep and wakefulness with rapid eye movement sleep intrusion into the wake state. In its classic form, seen in only 10% to 15% of cases, it is characterized by a tetrad of excessive daytime sleepiness, cataplexy (generalized muscle weakness leading to partial or complete collapse), hypnagogic/hypnopompic hallucinations (visual or auditory perceptions on falling asleep or on awakening), and sleep paralysis.
[1]American Academy of Sleep Medicine. International classification of sleep disorders - third edition (ICSD-3). 2014 [Internet publication].
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